Dimming switches come in different flavours, one is the range, often 40 - 200 watt or similar and if the LED total is too small they will not work, there is also leading and lagging, there are three ways to dim lights, variable resistor, variable transformer and wave form chopping, the first two need a large space and unlikely to be found in the home, and the latter can chop leading or lagging half of the wave form, with switch mode power supplies used for 12 volt lights leading or lagging matters as in real terms it tells the electronics in the switch mode power supply (electronic transformer) what to do, where the current regulator in a LED bulb is switch mode it may also matter, but in the main cheap dimmable LED lights use a simple capacitor to regulate current so it does not matter.
The most likely problem is the dimming switch is not designed to go that low in output.
Dimming switches need power, there are two methods to get power, one line to neutral, the other line in to line out, it drops the output just a small amount and uses that power to work the switch, so they can work without a neutral, however the electronics used can interfere with the lights, tungsten lights have a coil in them, so some inductance, and LED lamps a capacitor, but can interfere with the electronics of the lights, causing them to flicker, with LED some bulbs have a smoothing capacitor which stops the flicker, and some also have a resistor to leak away a little power so when an electronic switch turns off, or a two way switching has some capacitive leaking in the wires, the bulbs will not flash when switched off, so flicker and flashing can be a problem with some bulbs.
EU rules said any bulb which can't be dimmed must be marked
however it does not say they must say how they can be dimmed and the variable resistor or variable transformer may be able to dim the bulb but it can't be dimmed by wave chopping but it seems they don't need to tell you, the same with resistor to stop flashing when off, and the smoothing capacitor to stop the flicker, so it is a case of suck it and see.
Both the smaller of these bulbs says suitable for dimmer switch
the larger does not even give wattage or lumen output so breaks the EU rules, however the small bulb flashes when off with electronic switches and requires an external load capacitor and flickers when on, the large bulb works A1, the problem is with G9 lamps the old quartz required glass covers to catch the red hot bits should the bulb blow, and these covers will not fit on large bulb, so it changes the whole look of the chandelier they are fitted into.
But electronic switches be it simple remote controlled on/off or dimmers if not neutral used are a problem with some bulbs, the old BA22d, and E27 and even E14 don't seem to have a problem, but GU10 and G9 do.
In warm countries where LED or CFL saves energy, they used a different method, they would split lights into 1/3 and 2/3 on switches giving three levels of lighting, as they used CFL first which would not dim, their rooms were hot enough as it was without tungsten bulbs, so they moved to light only bulbs well before us, in this country likely the tungsten bulb saves energy, as it allows the air temperature of the room to be lower, due to the inferred heat from bulb, and since bulbs only used at night when the room was in use, it gave a natural evening boost to only rooms being used. However since gas and oil costs less than electric the CFL and LED did save money, but not energy.
Also quartz bulbs should not be dimmed, it reduces their life, as the quartz stays too cool and the tungsten adherers to the quartz instead of returning to the tungsten filament. Yes I know we did dim them, but we were not recommended to dim them, so any lamp designed to use quartz does not really need to be designed to dim, but using a dimmer as a soft start is different of course, and soft starts did seem to extend bulb life.
We do use wall lights, standard lamps, and table lamps in this country to adjust room lighting, there was at one time a circular fluorescent with two tubes where you could select output, but the standard chandelier does not seem to be designed for the 1/3 and 2/3 split, and if you turn 1/3 off it simply looks as if some bulbs have blown. In the same way as a fan built into a light can use a remote control to turn it on/off we could design a chandelier to do the same, but it seems we have gone for the dimmer switch.
What we need is for the
sign to mean leak off fitted and output smoothed suitable for an electronic switch as well as being dimmable, but that is not the case at the moment, and now we have left EU we could do it, but would not hold your breath.
So is there a certain type of dimmer switch I should try that would likely be compatible with LED bulbs? Or any dimmer that mentions it's for LED should be fine?
